Function modify

packages/effect-app/src/Pure.ts:200–208

(
  mod: (s: S2) => readonly [S3, A]
)

}

export function modify<S2, A, S3>(
  mod: (s: S2) => readonly [S3, A]
): Effect.Effect<A, never, { env: PureEnv<never, S2, S3> }> {
  return (castTag<never, S3, S2>()).useSync((_) => {
    const [s, a] = mod(_.env.state)
    _.env.state = s as any
    return a
  }) as any
}

export function modifyM<W, R, E, A, S2, S3>(
  mod: (s: S2) => Effect.Effect<readonly [S3, A], E, FixEnv<R, W, S2, S3>>